Many systems employ actuators to apply forces to objects. For example, smart matter systems or materials are physical objects having arrays of actuators for applying forces in response to the detection of changes in their environment. Smart matter can be used to move sheets of paper in a printing machine or maneuver an aircraft by performing tiny adjustments to wing surfaces. In the former example, actuators in the form of air jets apply forces to a sheet of paper to direct the motion of the sheet through the printing machine.
With the advent of low cost actuators such as those produced by batch fabrication, systems with large numbers of actuators are being contemplated. A major problem in such many actuator systems is addressing and controlling the actuators in a low cost manner. Matrix addressing may work for only some kinds of actuators, and in high density configurations, even this addressing scheme can result in too many costly connections to the controlling electronics. Moreover, the communication between the actuators and the controlling electronics can be expensive if it requires many channels of communication and individually controlled power.
For example, referring to FIG. 1, a conventional actuator array 4 is shown containing twenty-five actuators 6. Ten electrodes 8 control the actuators (for a general N×M array, N+M electrodes are used to control the actuators). To activate the actuator in the second row and third column, for example, an electrical signal is sent to this actuator using the electrode that controls the second row and the electrode that controls the third row.
In systems employing smart matter, which contain many actuators, running numerous electrodes to individually control each actuator can be expensive and unwieldy. Individual electrode lines must be routed into an array, drive electronics with a capability for handling each actuator must be built, and the actuation data rates must be correspondingly high, thereby loading down communication channels.